package python-poster (not installed) failed to install/upgrade: tentative de remplacement de « /usr/share/pyshared/poster/encode.py », qui appartient aussi au paquet opentumblr 0.1.0-1~getdeb2

While installing a lot of packages, using synaptic, I had the notification that a program stopped ...

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: python-poster (not installed)
ProcVersionSignature: Ubuntu 3.2.0-26.41-generic 3.2.19
Uname: Linux 3.2.0-26-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.0.1-0ubuntu8
Architecture: amd64
Date: Fri Jul 6 20:24:47 2012
ErrorMessage: tentative de remplacement de « /usr/share/pyshared/poster/encode.py », qui appartient aussi au paquet opentumblr 0.1.0-1~getdeb2
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
SourcePackage: python-poster
Title: package python-poster (not installed) failed to install/upgrade: tentative de remplacement de « /usr/share/pyshared/poster/encode.py », qui appartient aussi au paquet opentumblr 0.1.0-1~getdeb2
UpgradeStatus: No upgrade log present (probably fresh install)